The present invention relates to a connector-mounted substrate and a method for assembling the same. Particularly, the present invention relates to an improved connector-mounted structure in which a connector is connected with a circuit board using specially-designed rivets and an improved method for assembling the same.
In the conventional connector-mounted substrate disclosed in, for example, JP-A-61773/1992, rivets of which one ends have flanges are inserted into through holes formed in common in a connector and a circuit board and are securely caulked.
However, the above-mentioned prior art has the drawback in that the rivets cannot be handled with the surface mounting technology such as the soldering flow technology and that components other than the connector to be mounted on a circuit board must be mounted in a different process.
The conventional rivet is intended for the purpose of the caulking process only but lacks general versatility. The conventional rivet fixing method provides the poor reliability because of variations in dimension of the through hole. Moreover, addition of the engaging member proposed in the above-mentioned patent publication causes an increase in the number of constituent components.
The present invention is made to solve the abovementioned problems.
Moreover, the objective of the invention is to provide connector-mounted board using general-purpose rivets with improved shapes.
Furthermore, the objective of the present invention is to provide a circuit board assembling method for assembling a connector to a circuit board using improved rivets.
The objective of the present invention is achieved by a connector-mounted board using rivets each having a middle portion acting as a flange. The upper surface of the flange is closely fixed to a connector while the back surface thereof closely fixed to a circuit board.
For example, in a connector-mounted board where a connector with plural contact pins is attached to a circuit board with rivets, each of the rivets has one end fixed to the connector and the other end inserted into a first hole formed in the circuit board. The middle portion of the rivet has a flange securely fixed to the circuit board.
A land to be solder-bonded is preferably formed in the vicinity of the first hole formed in the surface of a circuit board so as to confront the flange. The land is solder-bonded to the flange. One advantage of the invention is that the solder bonding can be performed while other electronic components are being solder-bonded on the circuit board.
Moreover, according to the present invention, the connector-to-circuit board assembling method, wherein a connector with plural contact pins is mounted on a circuit board, comprises the steps of previously fixing one end of the rivet with a middle portion acting as a flange to the connector, inserting the other end of the rivet into a first hole formed in the surface of the circuit board, and then securely fixing said rivet to the circuit board by bonding said flange to said circuit board.
Particularly, according to the present invention, the rivet is formed of a hollow sleeve having a slit fitted and mechanically fixed to a hole formed in a circuit board and a flange having a flat portion. The rivet is attached to the substrate mounting portion of a housing by inserting one sleeve of the rivet into the hole formed in the substrate mounting portion and then caulking the sleeve. A connector is mounted to a circuit board by printing a soldering paste on the flat portion of the rivet and on the connector fixing pad formed on the circuit board and then by heating the intermediate structure.
In addition to the method of fixing the flat portion to the connector fixing pad, there are a method of inserting a hollow sleeve with a slit of a rivet into a hole formed in a circuit board, then supplying solder in the vicinity of the hollow sleeve from the back surface of the circuit board, and solder-bonding the follow sleeve to the substrate hole and to the other connector fixing pad formed on the back surface of the circuit board, and a method of inserting a hollow sleeve with a slit of a rivet into a hole formed in a circuit board, then caulking the hollow sleeve of the rivet on the back surface of the circuit board. The same connector can be mounted on a circuit board by performing one fixing method or selectively combining at least two of the above-mentioned three fixing methods according to mounting requirements, so that the versatility is improved.